Alginate Particles for Encapsulation of Phenolic Extract from Spirulina sp. LEB-18: Physicochemical Characterization and Assessment of In Vitro Gastrointestinal Behavior

Abstract

Encapsulation can be used as a strategy to protect and control the release of bioactive extracts. In this work, an extract from Spirulina sp. LEB-18, rich in phenolic compounds, was encapsulated in biopolymeric particles (i.e., composed of alginate) and characterized concerning their thermal behavior using differential scanning calorimetry (DSC), size, morphology, swelling index (S), and encapsulation efficiency (EE%); the release profile of the phenolic compounds at different pHs and the particle behavior under in vitro gastrointestinal digestion were also evaluated. It was shown that it is possible to encapsulate the phenolic extract from Spirulina sp. LEB-18 in alginate particles with high encapsulation efficiency (88.97%). It was also observed that the particles are amorphous and that the encapsulated phenolic compounds were released at a pH 7.2 but not at pH 1.5, which means that the alginate particles are able to protect the phenolic compounds from the harsh stomach conditions but lose their integrity under intestinal pH conditions. Regarding bioaccessibility, it was observed that the encapsulated phenolic compounds showed higher bioaccessibility compared to phenolic compounds in free form. This work increases the knowledge about the behavior of alginate particles encapsulating phenolic compounds during in vitro gastrointestinal digestion. It also provides essential information for designing biopolymeric particle formulations encapsulating phenolic compounds for application in pharmaceutical and food products.

Antioxidant and Antiradical Activities of Hibiscus sabdariffa L. Extracts Encapsulated in Calcium Alginate Spheres

“…The high viscosity of the alginate solution probably explains why these particles became spherical. It has been described that the gelation process can be impacted by the concentration of alginate solution [ 4 , 19 ] such that a higher concentration of this biopolymer (1–4%, w/w) molecules increases the number of cross-linking interactions with the bivalent ions and reinforces the structure of the matrix. Similar results were obtained by other authors.…”

“…Similar results were obtained by other authors. Machado et al (2022) [ 19 ] studied the encapsulation of phenolic extracts from spirulina sp. with alginate and reported spheres became more spherical at higher concentrations of sodium alginate.…”

Effect of Microencapsulated Basil Extract on Cream Cheese Quality and Stability

“…The encapsulation efficiency of the MBE was determined according to Machado et al [66]. Accordingly, 2.5 mg of beads and 5 mL of sodium citrate (3% w/v) were sonicated for 30 minutes.…”

Recent advances in oral delivery systems of resveratrol: foreseeing their use in functional foods

“…1,11,14 Currently, several materials (e.g., lipids, natural and synthetic polymers) and techniques (e.g., spray-drying, ionic gelation, electrohydrodynamic processing, and emulsification) are available for use in the food industry. [15][16][17][18][19][20][21] Different from other recent reviews focusing on multiple bioactives of plant origin and specific techniques for their delivery 22 or use in different areas (e.g., pharmaceutical, 23 biomedical, 24 and cosmetics 25 ), this review highlights the diverse delivery systems and techniques that can be used as oral delivery systems in food applications.…”

“…, spray-drying, ionic gelation, electrohydrodynamic processing, and emulsification) are available for use in the food industry. 15–21…”